Bacterial urinary tract infections (UTIs) are one of the most common reasons for children to be admitted to hospital. Bacteria infect and invade the bladder (the lower urinary tract) and if the infection disseminates to the upper urinary tract, significant inflammation in the kidneys may arise. Inflammation is a double-edged sword: it is needed to clear bacteria, but if excessive, kidney tissue is injured. During injury, nephrons are destroyed and replaced with deposition of extracellular matrix and a renal scar. In this review, we explore the pathogenesis of UTIs and discuss the risk factors that result in dissemination of bladder infection to the kidneys. Three major risk factors predispose to kidney infections: the presence of vesicoureteric reflux, the presence of bladder and bowel dysfunction, and defects in the ability of the host immune response to clear bacteria. In this review, we will discuss these factors, their relationship to renal scarring, and potential treatments that might be beneficial to prevent renal scar formation in children.

中文翻译：

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小儿输尿管反流和肾盂肾炎的肾脏瘢痕形成的发病机制和处理。

细菌性尿路感染（UTI）是儿童入院的最常见原因之一。细菌感染并侵入膀胱（下泌尿道），如果感染扩散到上泌尿道，可能会在肾脏中引起明显的炎症。炎症是一把双刃剑：它需要清除细菌，但是如果过多，肾脏组织会受到伤害。在受伤期间，肾单位被破坏并被细胞外基质和肾疤痕沉积所取代。在这篇综述中，我们探讨了泌尿道感染的发病机制，并讨论了导致膀胱感染向肾脏传播的危险因素。肾脏感染的三个主要危险因素：膀胱输尿管反流，膀胱和肠功能障碍，以及宿主对清除细菌的免疫反应能力的缺陷。在这篇综述中，我们将讨论这些因素，它们与肾脏瘢痕形成的关系以及可能有益于预防儿童肾脏瘢痕形成的潜在治疗方法。